/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * ----------------------
 * CenterArrangement.java
 * ----------------------
 * (C) Copyright 2005-2008, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * Changes:
 * --------
 * 08-Mar-2005 : Version 1 (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 20-Jul-2006 : Set bounds of contained block when arranging (DG);
 *
 */

package net.droidsolutions.droidcharts.core.block;

import java.io.Serializable;
import java.util.List;

import net.droidsolutions.droidcharts.awt.Rectangle2D;
import net.droidsolutions.droidcharts.common.Size2D;
import android.graphics.Canvas;

/**
 * Arranges a block in the center of its container. This class is immutable.
 */
public class CenterArrangement implements Arrangement, Serializable {

	/** For serialization. */
	private static final long serialVersionUID = -353308149220382047L;

	/**
	 * Creates a new instance.
	 */
	public CenterArrangement() {
	}

	/**
	 * Adds a block to be managed by this instance. This method is usually
	 * called by the {@link BlockContainer}, you shouldn't need to call it
	 * directly.
	 * 
	 * @param block
	 *            the block.
	 * @param key
	 *            a key that controls the position of the block.
	 */
	public void add(Block block, Object key) {
		// since the flow layout is relatively straightforward,
		// no information needs to be recorded here
	}

	/**
	 * Calculates and sets the bounds of all the items in the specified
	 * container, subject to the given constraint. The <code>Graphics2D</code>
	 * can be used by some items (particularly items containing text) to
	 * calculate sizing parameters.
	 * 
	 * @param container
	 *            the container whose items are being arranged.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the size constraint.
	 * 
	 * @return The size of the container after arrangement of the contents.
	 */
	public Size2D arrange(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {

		LengthConstraintType w = constraint.getWidthConstraintType();
		LengthConstraintType h = constraint.getHeightConstraintType();
		if (w == LengthConstraintType.NONE) {
			if (h == LengthConstraintType.NONE) {
				return arrangeNN(container, g2);
			} else if (h == LengthConstraintType.FIXED) {
				throw new RuntimeException("Not implemented.");
			} else if (h == LengthConstraintType.RANGE) {
				throw new RuntimeException("Not implemented.");
			}
		} else if (w == LengthConstraintType.FIXED) {
			if (h == LengthConstraintType.NONE) {
				return arrangeFN(container, g2, constraint);
			} else if (h == LengthConstraintType.FIXED) {
				throw new RuntimeException("Not implemented.");
			} else if (h == LengthConstraintType.RANGE) {
				throw new RuntimeException("Not implemented.");
			}
		} else if (w == LengthConstraintType.RANGE) {
			if (h == LengthConstraintType.NONE) {
				return arrangeRN(container, g2, constraint);
			} else if (h == LengthConstraintType.FIXED) {
				return arrangeRF(container, g2, constraint);
			} else if (h == LengthConstraintType.RANGE) {
				return arrangeRR(container, g2, constraint);
			}
		}
		throw new IllegalArgumentException("Unknown LengthConstraintType.");

	}

	/**
	 * Arranges the blocks in the container with a fixed width and no height
	 * constraint.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size.
	 */
	protected Size2D arrangeFN(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {

		List blocks = container.getBlocks();
		Block b = (Block) blocks.get(0);
		Size2D s = b.arrange(g2, RectangleConstraint.NONE);
		double width = constraint.getWidth();
		Rectangle2D bounds = new Rectangle2D.Double((width - s.width) / 2.0,
				0.0, s.width, s.height);
		b.setBounds(bounds);
		return new Size2D((width - s.width) / 2.0, s.height);
	}

	/**
	 * Arranges the blocks in the container with a fixed with and a range
	 * constraint on the height.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size following the arrangement.
	 */
	protected Size2D arrangeFR(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {

		Size2D s = arrangeFN(container, g2, constraint);
		if (constraint.getHeightRange().contains(s.height)) {
			return s;
		} else {
			RectangleConstraint c = constraint.toFixedHeight(constraint
					.getHeightRange().constrain(s.getHeight()));
			return arrangeFF(container, g2, c);
		}
	}

	/**
	 * Arranges the blocks in the container with the overall height and width
	 * specified as fixed constraints.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size following the arrangement.
	 */
	protected Size2D arrangeFF(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {

		// TODO: implement this properly
		return arrangeFN(container, g2, constraint);
	}

	/**
	 * Arranges the blocks with the overall width and height to fit within
	 * specified ranges.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size after the arrangement.
	 */
	protected Size2D arrangeRR(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {

		// first arrange without constraints, and see if this fits within
		// the required ranges...
		Size2D s1 = arrangeNN(container, g2);
		if (constraint.getWidthRange().contains(s1.width)) {
			return s1; // TODO: we didn't check the height yet
		} else {
			RectangleConstraint c = constraint.toFixedWidth(constraint
					.getWidthRange().getUpperBound());
			return arrangeFR(container, g2, c);
		}
	}

	/**
	 * Arranges the blocks in the container with a range constraint on the width
	 * and a fixed height.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size following the arrangement.
	 */
	protected Size2D arrangeRF(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {

		Size2D s = arrangeNF(container, g2, constraint);
		if (constraint.getWidthRange().contains(s.width)) {
			return s;
		} else {
			RectangleConstraint c = constraint.toFixedWidth(constraint
					.getWidthRange().constrain(s.getWidth()));
			return arrangeFF(container, g2, c);
		}
	}

	/**
	 * Arranges the block with a range constraint on the width, and no
	 * constraint on the height.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size following the arrangement.
	 */
	protected Size2D arrangeRN(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {
		// first arrange without constraints, then see if the width fits
		// within the required range...if not, call arrangeFN() at max width
		Size2D s1 = arrangeNN(container, g2);
		if (constraint.getWidthRange().contains(s1.width)) {
			return s1;
		} else {
			RectangleConstraint c = constraint.toFixedWidth(constraint
					.getWidthRange().getUpperBound());
			return arrangeFN(container, g2, c);
		}
	}

	/**
	 * Arranges the blocks without any constraints. This puts all blocks into a
	 * single row.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * 
	 * @return The size after the arrangement.
	 */
	protected Size2D arrangeNN(BlockContainer container, Canvas g2) {
		List blocks = container.getBlocks();
		Block b = (Block) blocks.get(0);
		Size2D s = b.arrange(g2, RectangleConstraint.NONE);
		b.setBounds(new Rectangle2D.Double(0.0, 0.0, s.width, s.height));
		return new Size2D(s.width, s.height);
	}

	/**
	 * Arranges the blocks with no width constraint and a fixed height
	 * constraint. This puts all blocks into a single row.
	 * 
	 * @param container
	 *            the container.
	 * @param g2
	 *            the graphics device.
	 * @param constraint
	 *            the constraint.
	 * 
	 * @return The size after the arrangement.
	 */
	protected Size2D arrangeNF(BlockContainer container, Canvas g2,
			RectangleConstraint constraint) {
		// TODO: for now we are ignoring the height constraint
		return arrangeNN(container, g2);
	}

	/**
	 * Clears any cached information.
	 */
	public void clear() {
		// no action required.
	}

	/**
	 * Tests this instance for equality with an arbitrary object.
	 * 
	 * @param obj
	 *            the object (<code>null</code> permitted).
	 * 
	 * @return A boolean.
	 */
	public boolean equals(Object obj) {
		if (obj == this) {
			return true;
		}
		if (!(obj instanceof CenterArrangement)) {
			return false;
		}
		return true;
	}

}
